1. Field of the Invention
The invention relates to an arrangement having a first peripheral device and a second peripheral device each having basic modules that are provided with process connections and accommodate electronic modules, where a redundancy adapter unit is provided for redundantly connecting a field device to a basic module of each of the two peripheral devices. The invention also relates to a redundancy adapter unit for such an arrangement.
2. Description of the Related Art
Siemens catalog “ST PCS 7—June 2012”, SIMATIC PCS 7 process control system, pages 8/2 to 8/6 discloses arrangements having peripheral devices. The peripheral devices in these arrangements are each provided with a multiplicity of assemblies mountable on a carrier, and are intended to connect the process peripherals to one or more automation devices. The assemblies usually each comprise a basic module (terminal module) and an electronic module, such as an electronic module comprising an I/O module, which can be plugged onto the basic module. Such a construction technique, with “fixed wiring”, supports pulling and plugging of the I/O peripheral modules during ongoing operation. For this purpose, the respective basic module that is mountable on the carrier is provided with line connections or channels for wiring process lines, which means that a sensor and/or an actuator can be connected to the respective line connections via a suitable process line.
In the environment of automation technology, there is an increasing requirement for highly available solutions that are suitable for minimizing possible downtimes of the installation. For this purpose, it is necessary to also design the assemblies of the peripheral device(s) in a redundant manner in addition to the CPU or central unit of an automation device. Therefore, signals from a sensor that are to be processed with respect to the peripheral devices are transmitted to two assemblies, or control signals for an actuator are transmitted to this actuator by two assemblies at the same time, where the wiring is effected such that a line connection of a basic module of one assembly is connected or short-circuited to the corresponding, identical, or matching line connection of a basic module of the other assembly using a line, and the sensor or actuator line is connected to one of these two line connections. In this context, the terms “corresponding, identical and matching” relate to the number, the positioning, the intended purpose, as well as to the mechanical and electrical design of the line connections of the basic modules.
If a field device (e.g., a sensor, an actuator or a measuring transducer) is intended to be redundantly operated in an assembly of a first peripheral device and in an assembly of a second peripheral device, it is possible to use a MTA terminal module which is known from the Siemens catalog “ST PCS 7”. The assemblies are connected, via two cables in the form of Y cabling, to the terminal module, to which the field device is connected, on the process side, via a connection cable. Here, the disadvantage is that this MTA terminal module is usually mounted on a top-hat rail and a separate space in a switchgear cabinet or in an installation must therefore be provided for this module.